Dude, it seems you don't understand the story at all. They are searching for a solution. It's science versus prophesy at the moment, guess you skipped that part.
Is the MC still infertile? I have no interest in continuing to play as long as the MC is infertile. I stopped playing when the biological mother gave the MC the good news that he was infertile. The entire plot involving impregnating the women on his home planet lost its meaning. In my opinion, it was a stupid idea from the developer. Why write a plot where the MC is the only man who can impregnate all the women on his home planet, and then it turns out he's infertile? So the entire trip to the planet and all the sex with the women who wanted a baby were pointless and a waste of resources, especially since the mother had him tested in the hospital on Earth. She should have discovered his infertility there, but apparently, the mother is as dumb as a doorknob and has no clue about biology. Otherwise, none of it makes any sense.
The entire plot involving the home world is simply poorly written and makes no sense; furthermore, it wastes rendering, and the developer has lost the plot.
I think the developer is too lazy to create models with baby bellies, so he made the MC infaltil, and pregnant women will only be seen in the epilogue.
(Translated with Google)